This invention relates in general to intravascular catheters, such as can be used during minimally invasive surgical procedures. In particular, this invention relates to an intravascular catheter having an expandable incising portion.
Atherosclerosis is a chronic condition in which atheromatous plaque accumulates on the inner walls of a blood vessel. As a result, the blood vessel walls can become inflamed and, over time, may harden to form atherosclerotic lesions that cause a narrowing of the vessel lumen. In severe cases, the atherosclerotic lesions can rupture and induce the formation of thrombus (i.e., blood clots), which can prevent blood flow through the narrowed vessel lumen.
There are known procedures and devices for treating or otherwise reducing the risks associated with atherosclerosis. For example, an angioplasty is a procedure in which a balloon catheter is inserted into a narrowed region of the vessel lumen via a delivery catheter. The balloon catheter includes a flexible tube having an inflatable balloon at an end thereof. Once positioned in the narrowed region, the balloon is inflated in order to dilate the narrowed vessel lumen. The pressure in the balloon is generally sufficient to compress the accumulated plaque. However, in some cases it would be desirable to fragment the atherosclerotic lesions. Thus, it would be desirable to provide an intravascular catheter having an expandable portion that can be selectively controlled by a user and adapted to create incisions in atherosclerotic material to facilitate fragmentation of the material during an angioplasty procedure.